Given the rise in the prevalence of childhood overweight and obesity, it is essential to develop nutritionally sound dietary strategies that prevent excessive weight gain and encourage the maintenance of healthy body weight in children. One dietary approach that has shown promise in adults involves varying the properties of foods that affect satiety and energy intake. For example, consuming foods that are reduced in dietary energy density (kcal/g) leads to decreased energy intake and improved diet quality in adults. Changes in the portion size and the variety of available foods can also affect energy intake. The proposed studies will extend these findings and determine how changes in foods and meals can be used strategically to moderate energy intake and improve diet quality in preschool children. The specific focus will be on reducing energy density and energy intake by increasing children's intake of vegetables at meals. In a series of crossover studies in [three] childcare centers, different strategies for influencing energy density and food intake will be tested by serving meals that are varied in portion size, variety, and meal structure. One strategy is to serve vegetables at the start of a meal when there are no competing foods available. It is hypothesized that vegetable intake will increase and that this effect will depend upon the portion served. Another strategy is to increase the proportion of vegetables served at meals. Public health organizations recommend this approach, and while it is likely to improve diet quality, its effect on energy intake has not been determined. Finally, the effect of increasing the variety of vegetables served at the meal will be assessed. The specific aims are to determine the effects on vegetable intake and energy intake of the following: 1) varying the portion size of vegetables served at the start of a meal;2) increasing the proportion of vegetables served during a meal either by adding extra vegetables or by substituting vegetables for other foods;and 3) increasing the variety of vegetables at the start of a meal or at the main course. In recent years there have been significant advances in understanding the influence of energy density, portion size, and variety of foods on energy intake and diet quality among adults, but much of this knowledge has not yet been extended to children. The proposed studies apply the findings from previous research on satiety in adults to advancing understanding of how the properties of foods and the structure of meals influence energy intake in preschool children. These data will translate to the development of specific strategies that can be adapted to children's energy needs and inform the design of effective public health messages to help prevent childhood obesity. PUBLIC HEALTH RELEVANCE: Because of the increasing rates of childhood overweight and obesity, there is an urgent need to find effective strategies that will help to reduce excess energy intake in children. The proposed studies will indicate how modifications in the portion size and variety of foods served at meals can be employed to increase vegetable intake, improve diet quality, and help to moderate energy intake in children. Such strategies will be of practical use in preventing childhood obesity and its serious consequences to health.